Ultra-high-frequency tube



March I27, 1945. c. v. L ITToN ULTRA-HIGH FREQUENCY TUBE Filed May l1,1940 y3 Sheets-Sheet l IIIIIIIL March 27, 1945. c. v. Lrr-roN 2,372,213

ULTRA-HIGH FREQUENCY TUBE AT RNEY.

March 27,A 1945, Q v, MT1-QN v 2,372,213

ULTRA-HIGH FREQUENCY TUBE Filed May 11, 1940 3 sheets-sheets PatentedMar. 27, 1.945

UNITED v sTATEs Y PATENT OFFICE ULTRA-HIGH-FREQUENCY TUBE charles v.Litton, Redwood city, Calif., assigoor to International StandardElectric Corporation', New York, N. Y., a corporation of DelawareApplication May 11, 1940, Serial `No. 334,535

2o claims. (ci. 25o-27.5)

My invention relates toultra-high frequency 'tubes and more specificallyto tubes having en-` velope structures adapted foruse in ultra-highfrequency circuits. l

Ultra-high frequency amplifiers and oscillators, q v

of the type wherein the groupingl of lelectrons into bundles dependingon their velocities is not the primary frequency determining factor, aresubject to frequency and power handling limitations, due to the circuitconstants of tuned cir-` cuits external to the amplifier or oscillatortube require small electrode structures. .By my inven-` tion Iy reducethese limitations of frequency and power handling capacity by formingthe tube envelope as a circuit of the resonant cavity type. With thistype of tube construction greater power `output and higher frequenciescan be obtainedV since increased electrode area and resonant cire cuitshaving a high Q are provided.

An object of my invention is to provide an ultra-high frequency tubehaving increased electrode areas.

A- further obect of my invention is to provide tionaly perspective ofthe oscillator tube of Fig. 1;`

Fig. 4 illustrates in sectional perspective an oscillator tube accordingto my invention;`

Fig. illustrates a modincation of the oscillator tube of Fig. 3; p Fig.6 illustratesin sectional perspective an amplifier tube according to myinvention.

In Fig. 1 a cavity type resonator in; the shape of a toroid forms themajor portion of the envelope of the tube I. A plate or anode 2 having atubular section 3 attached theretows sealed to the envelope I bymeans ofthe glass seal 4.

' Adjacent the plate 2 and sealed to the envelope or resonator is a grid5 which controls the number of electrons flowing from an indirectlyheated cathode 6to the plate. The cathode is heated by a filament 1supported by a= glass seal 8 which seals the cathode to thetubeenvelope. If desired, suitable direct current potentials may be appliedtothe grid by attaching a lead to the tube envelope, to the plate byattaching leads to the tubular extension 3, and to the cathode by meansofthe lead 9. l i v.tis is well known in the Aartthe resonator may andclose inter-electrode spacings which in turn' be tuned by varying the,physical dimensions thereof and a resonator of this type has aparticularly high Q. Accordingly, with this invention it is possible toprovide a varying high impedance circuit for the absorption of radiofrequency energy that may -be generated by the tube. This in turn `meansthat relatively high voltages can be used with consequent low time foright and hence much better performance may be obtained from anoscillator tube of this type than is possible with an oscillatortubehaving an external tuned circuit.

vFeedback between the plate of the tube and the tuned circuitgalvanically coupled to the grid is obtained by means of the capacitybetween the tubular extension 3 and the adjacent portion of the'resonant envelope. This tubular extension 3 also aids in thedissipation of heat from the plate.

'I'his tube with itsresonant circuit may be used in any well known highfrequencycircuits by taking the energy from the tube by means of thecoaxial line I0, sealed to the tube envelope by a seal II. y

Fig. 2 illustrates a modification of the tube of Fig. 1 which has alarger power handling capacity than the oscillator previously described.The symmetrical construction of the tube of Fig. 2 is especially adaptedto use as a Barkhausen type of oscillator having a positive grid and aplate that is negative with respect to the grid. In

this iigure, as in all the figures, similar reference numerals refer tocorresponding `parts of the tube structures. `An annular plate 2 havingdiscs 3 attached thereto is sealed to the resonant envelope I by meansof glass` seal 4.. A cathode 6 heated by a filament I issealed to theenvelope by means of the seal 8. Between the cathode 6 and the plate 2is a grid 5 directly attached to the tube envelope. By this toroidaltypek of construction large electron currents may be produced andutilized, thereby allowing large power output. As in the embodiment ofFig. 1 the output of the tube may be utilizedbymeans of the coaxial lineIIJ. V

In Fig. 3 is shown another modication o-f the embodiment of Fig. 1`wherein the grid 5 is insulated from the envelope I by the glass seal8. The grid is coupled to the resonant envelope by means of its tubularconstruction and proximity to the envelope. While in this gfure I haveshown the` plate 2 directly connected to the envelope and the gridcapacity .coupledthereta it is also possible toconstruct the'tube sothatboth the plate and the grid are coupled to the envel` ope. This type ofconstruction has the further advantage that it is necessary to form aseal only at only one part of the tube.

-It is apparent that the features of the modifications shown in Figs. 1and 3 could be combined with those of Fig. 2 to form a'tube in the shapeof two toroidal chambers, one tor-oid having an outer diameter smallerthan. the inner diameter of the other toroid, and the electrodes wouldthen be annular rings in horizontal planes rather than annular rings invertical planes as lshown in Fig. 2.

In Fig. 4 is illustrated an embodiment contain-- ing features of thetube described above. In thisVA figure is shown a ribbon type cathode I2 mounted on a glass rod I3 whose base terminates in a seal for the tubeenvelope I. Surrounding the cathode is a wound wire grid I4 mounted onrods I5. Surrounding the Wound wire grid is a tubular member I6 whichforms the `plate of the tube. The tubular member H51V is sealed to theresonant envelope I by means of seal 4f and as in the other embodimentsfeedback is obtained by the capacity betweenthe member I6 andtheresonant envelope I.

In the embodiments thus far described the entire tube envelope has beenexhausted. IThe removal of air from the envelopeA and the sealingthereof takes place in any well known manner and therefore need'y not bedescribed in detail herein. If. it is desired-'toavoid evacuating alarge chamber such as shown in Figs. 1 through 3, the tube structures ofthis invention may be formed in accordance with the embodiment of Fig.5. Fig. illustrates how the glass seal which sealsthe plate tothe tubeenvelope may be extended so that only the interior of thev tubular plateor anodeand a small portion of the.` remaining volume of the tube needbe exhausted. This glass seal is designated by reference numeral I'I.The glass rod I3 is supported by a: glassfootwhichextendsa, considerabledistance intothe. interior. ofy thev resonantk envelope, a seal4 beingeffected .by the base of the foot and the tube envelope. This type ofvtube construction-may be employed. with any. of the embodimentsdescribed, as is readily apparent' tothose* skilled: in the art.

In Fig.,6 Ihave shownan amplifier tube whose'V input IU' is fed fromaaseparate source. In this embodiment the tube envelope is.divided intotwo resonant chambers, I. andv I", which are provided for the plateandigrid, respectively. On the base of lthe. lower resonant chamber I ismounted a rod having an insulatorv I9: on the end .thereof whichsupports the ribben type'lcathode I2. Surrounding this cathode is. awound grid III` mounted on rods I5. andthe gridsis, inturn, surroundedby a tubular plate or anode I6. The output circuit of; thev tube isconnected to the upperl resonance chamber by a coaxialline I0, sealedthereto by seal II. Glassbeads 2II and 22 may be used to. seal thelcathode leads to the tube envelope.

In all of the embodiments-shown itis appar'- ent that the resonantenvelope or chamber is tuned to the operatingffrequency. It is alsoapparent that the tube describedin Fig. 6 may be usedA` as an oscillatortube by inter-coupling the input and output circuits.

In the various embodiments and modifications I have described particulartypes4 of cathodes and grids, but. other types of grids and cathodesknown to those skilled-,in the.' art may be substituted withoutdepartingfrom'thel scope of my invention.

While I have described particular embodiments of my invention forpurpose of illustration, it will be understood that variousmodifications and adaptations thereof may be made within the spirit ofthe invention as set forth in the appended claims.

What is claimed is:

1. Ahigh frequency tube including a conducting, toroidal resonant shellhaving a gap extending generally circumferentially of an inner portionof the surface of said toroidal shell, an anode sealed to said shell onone side of said gap and electrically insulated therefrom, said anodeincluding a generally cylindrical extension hav-ing` a diameter smallerthan the inner diameter of said shell and extending away from said gap,a portion of said cylindrical extension being longitudinally coextensivewith a portion of said shell, a cathode, and a grid connected to saidshell on the opposite side of said gap, said grid being positionedbetween said anode and said cathodel forc'ontrolling the number ofelectrons now-ing therebetween.

2. A high frequency tube according to'claim 1 whereinl a vacuum tightseal vof insulating material bridges'the gap and the portion of saidtube enclosing said grid is exhausted.

3. A high frequency tube according to claim 1 wherein said shell'` is'divided into an upper and lower section each having similar gaps, saidvcathode being sealed to said lower section below the lower of said gaps,and means for connecting external circuitsto 'said'l upperk and lowersections.

4. A high frequency tube including a conducting envelope'in the form ofresonant shells, said shells being in the shape of toroids havingannular gaps provided'in opposed adjacent surfaces thereof, anAannular'anode capacitatively coupled to said shells on one side of saidgaps, an annular cathode insulatingly sealed to said shells, and anannular grid coupled to said shells on the opposite side of said gaps,saidgrid being positioned between said. anode and said cathode forcontrolling the number of electrons flowing therebetween.

5. A high frequency. electron discharge device including a conducting.toroidal resonant shell having an annular gap in. a' portion of thesurface thereof, an anode insulatingly sealed to said shell on one sideofsaid'gap; said' anode including a portion spaced from andsubstantiallyparallel to the portion oflthe .surfaceofsaid'toroidal shell to whichsaid portion of. said, anode is sealed, a grid connected to the otherside ofsaid gap, and a cathode insulatedfromsaid shell.

A6. A high frequency electron discharge device having electrodesincluding a cathode, a grid, and

an anode, enclosing means ofconductive material' shells, and cathodemeanscommon to said two of said shells and sealedon the other side ofsaid gaps.

8.v A highfrequency electron discharge device is insulatingly sealed tovone side of said gaps and wherein coupling means is provided forcoupling i said anode to each of the shells to which it is common.

9. A high frequency `electron discharge device having a pair ofelectrodes including a substantially ring-,shaped cathode whose radiusis substantially greater than its axial dimension, an annular anodesurrounding the peripheryof and concentric with said cathode, and meansforming a hollow annular resonant chamber capacitatively coupled to andcoaxial with both of said electrodes.

1D. A high frequency electron discharge device comprising asubstantially ring-shaped cathode whose outer radius is substantiallygreater than its axial dimension, an annular grid surround ing theperiphery of and concentric with said cathode, an annular anodesurrounding and concentric with said annular grid, and means forming ahollow annular resonant chamber capacitatively coupled to said cathodeand directly con nected to said grid, and mounted coaxially with all ofsaid electrodes.

11. A high frequency electron discharge device having a pair ofelectrodes including a substantially ring-shaped cathode whose outerradius is more than approximately twice its longitudinal dimension, asecond ring-shaped electrode in the path of the electron stream fromsaid cathode. and surrounding the periphery of and concentric with saidcathode, means forming a. hollow annular resonant chamber coupled to andcoaxial with said electrodes, and sealed envelope-forming meansenclosing said electrodes.

12. The combination according to claim 11, in which 'said resonantchamber-forming means is capacitatively coupled to one electrode anddirectly connected to theother electrode.

13. The combination according to claim 11, in which said resonantchamber-forming means is forming a hollow annular 'resonant chambercoupled to said cathode and one of said other electrodes, and mountedco-axially with all of said electrodes,` and sealed envelope-formingmeans enclosing said electrodes. i

16. The combination according to claim 15, in which said resonantchamber-forming means is a conductive shell and forms a part of saidsealed envelope-forming means.

f including two juxtaposed longitudinally spaced capacitatively coupledto both of said electrodes.

14. The combination according to claim 11, in

. which said resonant chamber-formingmeans is comprising a substantiallyring-shaped cathode l whose outer radius is more than approximatelytwice its longitudinal dimension, a ring-shaped grid surrounding theperiphery of said cathode concentric with said cathode, a ring-shapedanode surrounding and concentric `with said grid. means conductingtoroidalshells having annular gaps in portions of the surface thereof,anode means common to said shells and connected thereto on one side ofsaid gaps, a substantially cylindrical control grid means, common tosaid two shells mounted within said anode' means, coaxial with said gridmeans, and means sealing said shells and forming an air-tight envelope.`

18. A high frequency tube having a conducting envelope, resonatorsforming part of said envelope,I said resonators being in the shape oftoroids having annular gaps provided in `opposed adjacent surfacesthereof, an annular anode coupled to said resonators on one side of saidgaps, a substantially ring-shaped cathode whose outer radius issubstantially greater than its longitudinal thickness coupled to saidresonators, and

an annular grid coupled to said resonators on opposite sides of saidgaps, said grid being positioned between said anode andsaid cathode forcontrolling the flow of electrons therebetween.

19. A high frequency tube including a conducting envelope, a hollowresonator forming part of said conducting envelope, a ring-shaped anodecoupled tc one side of said resonator, a substan` tially ring-shapedcathodewhose radius is more than approximately twice its longitudinaldimension, coupled vto the other side of said resonator, andaring-shaped grid. coupled to said resonator and positioned between saidanode and cathode for controlling the flow of electrons therebetween.20.- A high frequency electron discharge device, including a pair ofhollow resonators, ring-shaped anode means common to said resonators andcoupled to one side theref, ring-shaped grid means -common to saidresonators and mounted concentrically within said anode means, and asubstantially ring-shaped cathode whose'radius is more thanapproximately twice its longitudinal dimension, common to saidresonators and mounted concentrically within said grid means.

CHARLES V: LITTON.

CERTIFICATE 0F' CORRECTION.

Patent No. 2,572,215. March 27, 1915,

CHARLES V. LITTON.

It is hereby vcertified. that error appears in the printed specificationof the above numbered patent requiring `czorrecticn'l als follows: Page2, sec` ond column, line 62, claim 6, strike out -the Word"electrically" and insert the same before "coupling" in line Q4, sameclaim; and that the said Letters Patent should be read with thiscorrection therein that the same may co'rifom to the record of the casein the Patent Office.

Signed and sealed this 21st day of .Augustf A. D. 1914.5.

Leslie Frazer `(Seal) First Assistant Commissioner of' Patents.

